Arrangement for engaging and disengaging the mechanism controlling the movement of the needle-carrying bars in sewing machines provided with two needles



Feb. 19, 1963 BONO 3,077,346

' ARRANGEMENT FOR ENGAGING AND DISENGAGING THE MECHANISM CONTROLLING THE MOVEMENT OF THE NEEDLE-CARRYING BARS IN SEWING MACHINES PROVIDED WITH TWO NEEDLES Filed April 26, 1960 2 Sheets-Sheet 1 In e211? Lat L7 Brno Feb. 19, 1963 BONO 3, 4

ARRANGEMENT FOR ENGAGING AND DISENGAGING THE MECHANISM CONTROLLING THE MOVEMENT OF THE NEEDLE-CARRYING BARS IN SEWING MACHINES PROVIDED WITH TWO NEEDLES Filed April 26, 1960 2 Sheets-Sheet 2 Lul' i Bane United States Patent Efillfi ih Patented Feb. 19, 1953 hce 3377,34 6 ARRANGEMENT BEER EI'QGAGHNG AND GAGENG THE MECHANliSh l @GNTRGLLHNG THE MG'VEMENT FF THE NEELELECARRJKNG BARd W SEWHNG MAHINI3S PRGVHEED WHH TWD Luigi Bone, Favia, lltaiy, assignor to Necchi fiocieta per Aaioni, iE-avia, ltaiy, a company of ltaly Filed Apr. 26, 1969, Ser. No. 24-,735 Claims priority, nppiication itaiy lune 25, 1959 6 Claims. (63. 1ll2--221) The present invention relates to arrangements for engaging and disengaging the mechanism controlling the needle-carrying bar in a sewing machine provided with two needles.

The present invention has for its object to provide means for engaging and disengaging both needle-carrying bars and for disengaging selectively either of them by means of an arrangement which is extremely simple and compact and may be actuated even during the movement of a machine at a raised speed, said arrangement being particularly intended for incorporation with sewing machines shifting the fabric through the needle tips and wherein the needle-carrying bars are subjected to rocking movements in a vertical plane extending in the sewing direction.

The arrangement forming the object of the present invention is characterized more particularly by the fact that the means cooperating in the engagement and disengagement of the mechanism controlling the bars and their stopping at a predetermined height are carried by a r d parallel with said bars and fitted on the support carrying the latter. Such a rod assumes a reciprocatory movement with the needle-carrying bars and controls the engagement, disengagement and stopping of the latter through limited rotations of said bar round its own axis. Said rotations are obtained through suitable transmission means, including an elastic member and controlled by a handle or grip carried by the arm of the sewing machine.

The accompanying drawings illustrate, by way of a mere example, and by no means in a binding sense, a. preferred embodiment of the invention which will be described hereinafter with reference to said drawings, in which:

FIG. 1 is a front view of a sewing machine incorporating the improved arrangement.

FIG. 2 is a front view of the same machine.

FIG. 3 is a view from above of the same machine.

FIG. 4 is a front view of the needle-carrying bars.

FIG. 5 is a view of said bars from above.

FIG. 6 is a cross-section of said bars through line Vl-VI of FIG. 4.

FIG. 7 is a lateral view of the arrangement shown during the disengagement of the left-hand needle carrying bar.

PKG. 8 is a cross-section on an enlarged scale of the arrangement according to line VIHVHI of FIG. 7.

FIG. 9 is a cross-section of the arrangement on a different scale through line lXlX of PEG. 7.

FIG. 10 shows the same cross-section as that of FIG. 9, but wherein the right-hand needle-carrying bar is disengaged.

The needle-carrying bare are illustrated in the drawings at 1 and 1 and are guided in the sleeves 2 and 3 rigid with the support 4 and slide freely inside the connecting member 5 secured to the lower end of a rod 6 extending in parallelism with the bars 1 and l and slidingly carried by an upper sleeve 7 rigid with the same support 4 and two lower sleeves 8 and 9 rigid with said support through the agency of the sleeve for instance.

The connecting member 5 bestows the rod 6 with the conventional reciprocating movement to be transmitted by the latter to either or both the needle-carrying bars.

The support for the sleeves is secured to the frame of the machine through the agency of an angularly shiftable pivot lib adapted to execute in a conventional manner the oscillations required, so that the needles may cooperate in the shifting of the material to be sewn and which is carried by the lower surface 11 of the machine.

it should, of course, be understood that, without unduly widening the scope of the invention as defined in the accompanying claims, it is possible to make the sleeve support 4 rigid with the frame of a sewing machine in which no shifting of the fabric by the needle tips is required.

The needle-carrying bars 1 and 1' have a semi-circular cross-section and they face each other through their flat surfaces, as illustrated in FIGS. 4, 5 and 6. However, they may assume cross-sections which are different from those already described and they may slide inside sleeves independently provided for each bar. In such an arrangemenh'it is possible to provide, within the scope of the invention as defined, the engagement and disengagement in the manner described in detail hereinafter, with suitable modifications in the outline of a driving member 12 and a holding member 13 controlled by the r d 6 and adapted to drive and stop respectively the needlecarrying bars.

Said needle-carrying bars 1 and 1 are provided at suitable points with transverse cuts, respectively at 14, 15 and 14', 15 so as to form bearing surfaces adapted to receive the above-mentioned driving member 12 at 14-14 and the holding member 13 at 15-15. The longitudinal guiding grooves 16, 17 or 16', 17 have for their object to further facilitate the engagement of said members 12 and 13 inside the transverse cuts of the corresponding bars 1 and 1.

Collars having rectangular cross-sections 18 and 18' are provided for the purpose of preventing any rotation of the bars inside their sleeves by reason of the contact of the connecting member 5 through its shoulders 19 with said collars whereby said connecting member is adapted to urge upwardly the bars until impact thereof against the stop 2%.

At the lower end of the rod 6 and above the connecting member 5 is secured the driving member 12; in the upper end of said bar s is formed a longitudinal groove it inside which are freely fitted the teeth 22 on the holding member 13 which is mounted in a fixed axial position between the guides 8 and S and can rotate about its axis while the tooth 23 on the upper sleeve 7 also engages freely said longitudinal groove 21.

Thus, the rod 6 may be subjected to a rotation round its own axis, the amplitude of which rotation is the same as that of the movement transmitted to the sleeve 7 which is provided to this end with a toothed sector 24- meshing with the toothed sector 25 rigid with the lever 26 controlled by the handle 31 through the kinematic chain 2.728--293.

There is a suiiicient clearance between the toothed sectors 24 and 25, so that the sleeve support 4 may execute round its pivot it the oscillation required for the shifting of the fabric by the needle tips.

The amplitude of the rotation of the rod 6 is limited by the stop 32 secured to the sleeve support 4, which stop 32 is adapted to impinge against the projections 33 and 3-4 on the toothed sector 24 so as to limit the rotation of the latter.

Such rotations are possible only when the driving member 12 and the holding member 13 register with the transverse cuts formed in the needle-carrying bars. 1n the opposite case, the movements imparted to the handle earners 6 31, instead of being transformed into rotations of the rod 6 are transformed into deformations of the spring 28. This will be described with further detail hereinafter.

During normal sewing with two needles, the control handle 31 is arranged in a central position C and the driving member 12 acting as a clutch and carried at the lower end of the bar 6 engages simultaneously the cuts 14 and 14' formed in the two needle-carrying bars 1 and 1', so that said member 12 may transmit to the bars the downward movement of the rod 6. On the contrary, the upward movement is controlled, as mentioned hereinabove, by the engagement of the connecting member with the collars 18 and 18' of the needle-carrying bar. Such an upward movement may furthermore be obtained directly, if required, by the driving member 12.

The needle'carrying bars are therefore subjected to the normal reciprocation required for actual sewing, while the holding member 13 is inoperative.

In order to disengage the needle-carrying bar 1 on the left-hand side, it is necessary to set the control member in its right-hand position, D. Conversely, the disengagement of the right hand needle-carrying bar 1' is obtained by shifting the handle into its left position S. The disengagement is obtained in a similar manner in both cases so that it is sufiicient to describe the disengagement of the bar 1. The shifting of the handle 31 into the position D, urges through the kinematic chain 30, 29, 23, 27 the lever 26 into rotation round its own pivot 35 carried by the frame of the machine.

The toothed sector 25 on said lever 26 is coupled with a similar toothed sector 24 on the sleeve 7 so that the latter rotatesand produces through the rod 6 an angular shifting of the driving member 12 and that of the holding member 13. However, said rotation is possible only when the needle-carrying bars 1 and 1' reach their upper dead center for which position the transverse cuts 15 and 15' in said bars register with the stopping member 13. Until this is achieved, the shifting of the handle 31 into the position D produces a deformation of the spring 28 and causes the tip 36 of the holding member 13 to exert a pressure inside the longitudinal groove 17 in the bar 1.

When the needle-carrying bars reach their upper dead center, the tip 36 of the member 13 engages the transverse cut 15 in the needle-carrying bar, and, at the same time, the driving member 12 releases the transverse cut 14 in the same bar whereby the spring 28 is allowed to expand again. This causes the driving member 12 to urge downwardly the needle-carrying bar 1' alone while the needle-carrying bar 1 remains stationary in its upper dead center. In order to make the needle-carrying bar 1 resume its movement, it is necessary to return the handle 31 into its central position C. To this end, it is sufficient to shift it slightly forwardly, so that the lever 31) may disengage the step 37 on the control plate 38 and may be returned automatically into its central position under the action of the spring 39, which, being tensioned by the preceding operation, expands now.

The spring 39' arranged symmetrically with reference to the spring 39 produces, in the opposite direction, the same operations as said spring 39 and it is tensioned when the handle 31 is shifted into its left hand position S so as to expand upon returning of the handle into its central position.

In the embodiment illustrated, the springs 39 and 39 are actually constituted by the two ends of a single spring wound round the aXis of the pivot 29. Said spring ends ride over a further pivot 40 secured to the frame of the machine and engage the lever 30. In all cases, the shifting of the handle 31 out of the position D into the position C produces a deformation of the spring 28 when it is attempted to turn the driving and holding members.

This produces a pressure of the sidewall 40 (FIG. 9)

of the driving member 12 against the longitudinal groove 16 in the needle-carrying bar. When said bar reaches its upper dead center, the driving member 12 engages again, in addition to the cut 14, the cut 14, while the holding member 13 shifts its tip 36 out of the cut 15, the spring 23 being then released and expanding. Thus both needle-carrying bars will now follow the movement of the rod 6.

I claim:

1. In a sewing machine of the double needle type, two identical needle bars, bearings mounting said needle bars in side-by-side relation for reciprocation, a rod disposed immediately adjacent said needle bars in parallel relation thereto, bearings mounting said rod for axial reciprocation and rotation about the axis thereof, a drive member connected to said rod for effecting the reciprocatory movement thereof, each. of said needle bars having a first transverse recess and a second transverse recess, a driving member carried by said rod for reciprocation and rotation therewith, and selectively engaged in said first recesses to selectively connect at least one of saidneedle bars to said rod for reciprocation therewith, a holding member selectively engageable in said second recesses to lock a selected one of said needle bars in a retracted inoperative position, means mounting said holding member for rotation and retaining the same against movement axial with said rod, said rod slidably passing through said holding member and being connected to said holding member for rotation therewith, and means for rotating said rod to selected needle bar holding and driving positions.

2. The sewing machine of claim 1 wherein said holding member has circumferentially spaced second recess engaging portions, and said driving member has an elongated first recess engaging portion aligned with the space between said second recess engaging portions, whereby a needle bar is always engaged by one only of said driving member and said holding member in a selected rotated position of said rod.

3. The sewing machine of claim 1 wherein said needle bars have flat opposed faces, and single ones of said needle bar bearings supporting both of said needle bars.

4. The sewing machine of claim 1 wherein said needle bar bearings and said rod bearings each include an upper bearing, and means pivotally mounting said upper bearings to permit tilting of said needle bars and said rod as said needle bars and said rod reciprocate, whereby needles carried by said needle bars will effect the shifting of material.

5. The sewing machine of claim 1 wherein said means for rotating said rod includes a gear segment connected to the upper part of said rod, a drive pinion engaged with said gear segment, and means for rotating said drive pinion.

6. The sewing machine of claim 5 wherein said means for driving said drive pinion includes a manually positionable handle aud an elastic drive element between said handle and said drive pinion whereby said handle may be shifted to a selected needle bar driving position without movement of said rod, said gear segment and said drive pinion until said needle bar recesses are aligned with said driving member and said holding member at which time said elastic drive element will efi'ect the rotation of said rod to a position corresponding to the position of said handle.

References Cited in the file of this patent UNITED STATES PATENTS 602,988 Jerram Apr. 26, 1898 1,672,353 Tomich June 5, 1928 1,754,608 Card Apr. 15, 1930 2,832,301 Wear Apr. 29, 1958 2,868,152 Benink et a1 Jan. 13, 1959 2,871,810 Quitter Feb. 3, 1959 

1. IN A SEWING MACHINE OF THE DOUBLE NEEDLE TYPE, TWO IDENTICAL NEEDLE BARS, BEARINGS MOUNTING SAID NEEDLE BARS IN SIDE-BY-SIDE RELATION FOR RECIPROCATION, A ROD DISPOSED IMMEDIATELY ADJACENT SAID NEEDLE BARS IN PARALLEL RELATION THERETO, BEARINGS MOUNTING SAID ROD FOR AXIAL RECIPROCATION AND ROTATION ABOUT THE AXIS THEREOF, A DRIVE MEMBER CONNECTED TO SAID ROD FOR EFFECTING THE RECIPROCATORY MOVEMENT THEREOF, EACH OF SAID NEEDLE BARS HAVING A FIRST TRANSVERSE RECESS AND A SECOND TRANSVERSE RECESS, A DRIVING MEMBER CARRIED BY SAID ROD FOR RECIPROCATION AND ROTATION THEREWITH, AND SELECTIVELY ENGAGED IN SAID FIRST RECESSES TO SELECTIVELY CONNECT AT LEAST ONE OF SAID NEEDLE BARS TO SAID ROD FOR RECIPROCATION THEREWITH, A HOLDING MEMBER SELECTIVELY ENGAGEABLE IN SAID SECOND RECESSES TO LOCK A SELECTED ONE OF SAID NEEDLE BARS IN A RETRACTED INOPERATIVE POSITION, MEANS MOUNTING SAID HOLDING MEMBER FOR ROTATION AND RETAINING THE SAME AGAINST MOVEMENT AXIAL WITH SAID ROD, SAID ROD SLIDABLY PASSING THROUGH SAID HOLDING MEMBER AND BEING CONNECTED TO SAID HOLDING MEMBER FOR ROTATION THEREWITH, AND MEANS FOR ROTATING SAID ROD TO SELECTED NEEDLE BAR HOLDING AND DRIVING POSITIONS. 